A File-Distribution Approach to Achieve High Availability and Confidentiality for Data Storage on Multi-cloud

Cloud services are rapidly increasing. We usually use only one cloud service. However, today costs of using cloud service become lower, so we can use multiple cloud services simultaneously. In these environments, there appear possibilities to improve confidentiality and availability by using multiple hetero cloud services. Based on a "secret sharing scheme, " a new approach to attain extremely high confidentiality and high availability at reasonable cost is proposed. With this approach, multiple optimal clouds for storage are dynamically determined in accordance with each file and cloud SLA (service level agreement). Furthermore, the reliability of the proposed approach is quantitatively demonstrated by using an evaluation model in the case of homo cloud services.